is reused and the numbers are much higher, 50,000, 100,000, 200,000 gallons a day, imagine the savings on that that you're getting. you're not purchasing freshwater and you're not using the sewer and being charged appropriately. this wastewater processing and reuse technology is cutting edge. and although it's been successfully implemented in other cities, it will be one of the first such installations in an urban office building. >> here is a city agency that treats wastewater, but they send no wastewater to the treatment facility. that says a lot. >> it's got a 12 gallon per day occupancy using 5,000 gallons per day with a building officing 1,000 people. that turns out to save over 2.7 million gallons a year. >> the public utilities commission runs water, power and sewer services for san francisco. we can't afford to be out of business after an earthquake.